1. Field of the Invention
The field of the invention is oral conduits for fluids, including oral airways.
2. Background Art
Nasal Breathing Restrictions.
Some persons at times breathe nasally during sleep, with the lips and jaws closed, thereby eliminating the mouth as an effective airway. Closed-mouth, nasal breathing through restricted nasal air ways reduces ventilation volume and can impair breathing and sleep. Restrictions in the nasal airway path may significantly contribute to breathing insufficiency during sleep in some persons who breathe nasally with lips closed. Scientific and medical experts have reported (or hypothesized) a variety of contributing and causal factors other than nasal airway restriction for hypopnea and apnea, such as sagging of the base of the tongue, and possibly the lower jaw, towards the throat, resulting in restriction or blockage of the throat air way. Nasal restrictions may contribute to snoring and to sleep apnea.
Jaw and Tongue Control Devices.
A variety of devices has been developed and patented by others to mechanically control a user's jaw and tongue positions to minimize sagging of tongue and mandible towards the user's throat airway. Some include oral airways. Others are designed to function during closed-mouth, nasal breathing.
It is an objective of the instant cheek airway invention that it be capable of placement and use in combination with a wide variety of exiting jaw- and tongue-control devices, though perhaps with some modification of such devices.
Tongue-Control Devices.
A non-exhaustive list of examples of tongue-control devices that incorporate airways or employ positive or negative air pressure is:
Alvarez, et al., U.S. Pat. No. 5,465,734 (1995); Hart, U.S. Pat. No. 5,957,133 (1999); Karell, U.S. Pat. No. 6,408,851 B1, discloses a tongue-fastening device having airway 40 and two or more internal airway openings 42 which, as depicted in Karell's FIGS. 3 and 5, pass between the teeth. Kulick, Pub. No.: US 2002/0139375 A1 holds the tongue forward by suction, uses bite blocks 2 to prevent biting the tongue and support air passages 4 into the oral cavity. Nelson, U.S. Pat. 6,244,865 B1, discloses a tongue positioning device which includes a hollow passageway 20 in the mouthpiece for flow of breathing gases into the mouth.
Mouthpieces and Lip-Passing Tubes.
There exists an enormous variety of mouthpieces and other devices for delivery of gases past the user's lips into the user's mouth. Examples include snorkels and SCUBA (Self-Contained Underwater Breathing Apparatus) mouthpieces, as well as tubes, cannulae and ventilators used in medicine, surgery, anaesthesia, orthodontics, and sports. There also are numerous devices designed to ameliorate some aspect of nasal congestion, snoring, hypopnea and apnea. Some airway devices simply provide conduits to external air at ambient pressure, whereas others are designed to deliver gases at modified pressures. Examples of the latter are CPAP (Continuous Positive Airway Pressure) and BiPAP (Bi-level Positive Airway Pressure) machines.
Many existing oral airways pass between a user's maxillary and mandibular teeth, requiring bite blocks or other devices to prevent crushing of the airway between the teeth and thus restricting the user's jaw motion.
Devices Using Portions of the Cheek Pathway.
Nelson, in a series of U.S. Pat. No. 4,170,230, (1979), U.S. Pat. No. 4,261,354 (1981), U.S. Pat. No. 4,262,666 (1981) and U.S. Pat. No. 4,289,127 (1981), discloses several different versions of hollow tubes which traverse portions of a user's cheek pathway. Nelson's devices are designed for stand-alone cheek-side positioning; that is, they are not anchored to teeth-engaging or palate-engaging dental devices. Nelson does not disclose any structure curving around a user's rear-tooth corner, or passing into or through a user's rear-jaw gap, or extending from the user's rear-jaw gap over the user's tongue into airspace in a user's rear-mouth cavity. Nelson describes and depicts his curved tube as open-ended, with at least one opening internal to the user's mouth, and having a length to insure that there will be an air flow opening approximate the molars at the rear of the user's mouth. See, for example, Nelson, U.S. Pat. No. 4,170,230, abstract; column 1:25-38; column 2:55-67; column 3:19-35; column 4: 5-14; claims 1 and 6; and FIGS. 1, 2, 3, 5 and 7. Nelson's disclosure states that the air flow opening(s) of Nelson's tube “pass the air from the tube to the rear of the mouth and upper trachea.” Since Nelson does not disclose any tube structure dorsal of the user's molars, Nelson leaves a reader to guess the path which air traverses after exiting Nelson's tube “approximate the molars.” Nelson, U.S. Pat. No. 4,170,230, column 1, lines 44-47; column 4, lines 5-13; and abstract.
Nelson's patents, and especially U.S. Pat. No. 4,289,127 (1981), also disclose various cheek-side stabilizing devices including fin-like, wire-like and rod devices. Nelson describes his cheek-side stabilizing devices as rigid or flexible or malleable, but does not describe them as resilient or spring-like.
Pope and Hawkins, U.S. Pat. No. 4,553,549, disclose a “pressure equalization conduit” attached to an orthopedic/orthodontic appliance for treating neuromuscular imbalance which is positioned “so that the tube extends along the outside surface of the teeth around the posterior of the teeth to the position which is in communication with the pharyngeal cavity.” Pope, et al., U.S. Pat. No. 4,553,549, specification col. 3:10-20 and claim 13. (Pope's “posterior” presumably corresponds to dorsal.) In contrast with Nelson's cheek-side tubes, the pressure equalization conduit of Pope, et al., is not disclosed as a self-contained device designed to stand alone in a cheek pathway. Rather, the Pope conduit is positioned by wire holders that are embedded in the teeth- and palate-engaging elements of the Pope orthopedic/orthodontic device. Pope et al. U.S. Pat. No. 4,553,549, col. 5:60-68. At least one version of the Pope conduit is disclosed and is explicitly claimed as having “inside diameter of from about 2 to 3 mm.” Pope, Specification, 3:30-40 and claim 16. However, Pope, et al. do not state limiting diameters.